Inputs

List of inputs of EPW v5.3

Note

In this page, you can find the documentation on the inputs variables of the current version (v5.3) of EPW. The documentation on the inputs variables of the previous version (v5.2) of EPW can be found here.

Structure of the input data

title_line

&inputepw

/

nqs {cartesian}

xq(1) xq(2) xq(3) wq

Note: the k/q-points of the fine grids have to be provided in crystal coordinate only.

a2f

Type

LOGICAL

Default

.false.

Description

Calculate Eliashberg spectral function, \(\alpha^2F(\omega)\), transport Eliashberg spectral function \(\alpha^2 F_{\rm tr}(\omega)\), and phonon density of states \(F(\omega)\). Only allowed in the case of phonselfen = .true.

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amass(:)

Variable

amass(i), i=1,ntyp

Type

REAL

Default

0.0

Description

Atomic mass [amu] of each atomic type. If not specified, masses are read from data file.

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asr_typ

Type

CHARACTER

Default

‘simple’

Description

Kind of acoustic sum rule that can be imposed in real space. Possible ASR are ‘simple’, ‘crystal’, ‘one-dim’ and ‘zero-dim’.

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assume_metal

Type

LOGICAL

Default

.false.

Description

Assume we have a metal. This flag should only be activated in the context of transport (conductivity or resistivity) calculations. In that case use a Fermi-Dirac distribution.

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band_plot

Type

LOGICAL

Default

.false.

Description

Writes files for band structure and phonon dispersion plots. The k-path and q-path is provided using filkf and filqf.

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bands_skipped

Type

CHARACTER

Default

''

Description

List of bands to exclude from the wannierization, where the number of excluded bands should be smaller or equal to nbndskip. For example, bands_skipped = 'exclude_bands = 1:5' means the first 5 bands are excluded from the wannierization.

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bnd_cum

Type

INTEGER

Default

1

Description

Band index for which the cumulant calculation is done. For more than one band, you need to perform multiple calculation and add the results together.

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broyden_beta

Type

REAL

Default

0.7

Description

Mixing factor for Broyden mixing scheme.

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broyden_ndim

Type

INTEGER

Default

8

Description

Number of iterations used in the Broyden mixing scheme.

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carrier

Type

LOGICAL

Default

.false.

Description

If .true. it computes the intrinsic electron or hole mobility such that the carrier concentration is given by ncarrier.

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conv_thr_iaxis

Type

REAL

Default

1.d-05

Description

Convergence threshold for iterative solution of imaginary-axis Eliashberg equations.

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conv_thr_racon

Type

REAL

Default

5.d-05

Description

Convergence threshold for iterative solution of the analytic continuation of Eliashberg equations from imaginary- to real-axis.

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conv_thr_raxis

Type

REAL

Default

5.d-04

Description

Convergence threshold for iterative solution of real-axis Eliashberg equations.

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cumulant

Type

LOGICAL

Default

.false.

Description

If .true. calculates the electron spectral function using the cumulant expansion method. Can be used as independent postprocessing by setting ep_coupling =.false.

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degaussq

Type

REAL

Default

0.05

Description

Smearing for sum over q in the e-ph coupling in [meV]

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degaussw

Type

REAL

Default

0.025

Description

Smearing in the energy-conserving delta functions in [eV]

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delta_approx

Type

LOGICAL

Default

.false.

Description

If .true. the double delta approximation is used to compute the phonon self-energy.

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delta_qsmear

Type

REAL

Default

0.05

Description

Change in the energy for each additional smearing in the a2f in [meV].

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delta_smear

Type

REAL

Default

0.01

Description

Change in the energy for each additional smearing in the phonon self-energy in [eV]

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dvscf_dir

Type

CHARACTER

Default

‘./’

Description

Directory where ‘prefix.[dvscf|dyn]_q??’ files are located.

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efermi_read

Type

LOGICAL

Default

.false.

Description

If .true. the Fermi energy is read from the input file.

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eig_read

Type

LOGICAL

Default

.false.

Description

If .true. then read a set of eigenvalues from ksdata.fmt. Can be used to read GW (or other) eigenenergies. The code expect a file called “prefix.eig” to be read. One need to provide the same number of bands as in the nscf calculations and all k-points.

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elecselfen

Type

LOGICAL

Default

.false.

Description

Calculate the electron self-energy from the el-ph interaction

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eliashberg

Type

LOGICAL

Default

.false.

Description

If .true. solve the Eliashberg equations and/or calculate the Eliashberg spectral function.
1) if laniso =.true., the anisotropic Eliashberg equations are solved. This requires that .ephmat, .freq, .egnv, .ikmap files are read from the disk. The files are written when ephwrite =.true. in the input file (see ephwrite variable).
2) if liso =.true., the isotropic Eliashberg equations are solved. This requires that either (a) .ephmat, .freq, .egnv, .ikmap files (see ephwrite variable) or (b) isotropic Eliashberg spectral function file (see fila2f variable) are read from the disk.
3) if .not. laniso and .not. liso , the Eliashberg spectral function is calculated. This requires that .ephmat, .freq, .egnv, .ikmap files are read from the disk. The files are written when ephwrite =.true. in the input file (see ephwrite variable).
Note: To reuse .ephmat, .freq, .egnv, .ikmap files obtained in a previous run, one needs to set ep_coupling =.false., elph =.false., and ephwrite =.false. in the input file.

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elph

Type

LOGICAL

Default

.false.

Description

If .true. calculate e-ph coefficients.

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ep_coupling

Type

LOGICAL

Default

.true.

Description

If .true. run e-ph coupling calculation.

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epbwrite, epbread

Type

LOGICAL

Default

.false.

Description

If epbwrite = .true., the electron-phonon matrix elements in the coarse Bloch representation and relevant data (dyn matrices) are written to disk. If epbread = .true. the above quantities are read from the ‘prefix.epb’ files. Pool dependent files.

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epexst

Type

LOGICAL

Default

.false.

Description

If .true. then prefix.epmatwp files are already on disk (don’t recalculate). This is a debugging parameter.

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ephwrite

Type

LOGICAL

Default

.false.

Description

Writes 4 files that are required when solving the Eliashberg equations. .ephmat files with e-ph matrix elements within the Fermi window (fsthick) on fine k and q meshes on the disk. .ephmat are pool dependent files. .freq file contains the phonon frequencies; .egnv file contains the eigenvalues within the Fermi window, and .ikmap file contains the index of the k-point on the irreducible grid within the Fermi window. These files are required to solve the Eliashberg equations when eliashberg = .true.. The files can be reused for subsequent evaluations of the Eliashberg equations at different temperatures. ephwrite doesn’t work with random k- or q-meshes and requires nkf1,nkf2,nkf3 to be multiple of nqf1,nqf2,nqf3.

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eps_acustic

Type

REAL

Default

5.d0

Description

The lower boundary for the phonon frequency in el-ph and a2f calculations in [cm-1].

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epsiHEG

Type

REAL

Default

0.25d0

Description

Dielectric constant at zero doping for electron-plasmon.

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epwread

Type

LOGICAL

Default

.false.

Description

If epwread = .true., the electron-phonon matrix elements in the coarse Wannier representation are read from the ‘epwdata.fmt’ and ‘XX.epmatwpX’ files. Each pool reads the same file. It is used for a restart calculation and requires kmaps = .true. A prior calculation with epwwrite = .true is also required.

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epwwrite

Type

LOGICAL

Default

.true.

Description

If epwwrite = .true., the electron-phonon matrix elements in the coarse Wannier representation and relevant data (dyn matrices) are written to disk. Each pool reads the same file.

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etf_mem

Type

INTEGER

Default

1

Description

If etf_mem = 0, then all the fine Bloch-space el-ph matrix elements are stored in memory (faster). When etf_mem = 1, more IO (slower) but less memory is required. When etf_mem = 2, an additional loop is done on mode for the fine grid interpolation part. This reduces the memory further by a factor “nmodes”.

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fermi_diff

Type

REAL

Default

1.d0

Description

Difference between Fermi energy and band edge (in eV). Only relevant when lscreen = .true.

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fermi_energy

Type

REAL

Default

0.d0

Description

Value of the Fermi energy read from the input file in [eV].

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fila2f

Type

CHARACTER

Default

''

Description

Input file with isotropic Eliashberg spectral function. The file contains the Eliashberg spectral function as a function of frequency in [meV]. This file can only be used to calculate the isotropic Eliashberg equations. In this case *.ephmat, *.freq, *.egnv, and *.ikmap files are not required.

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fildvscf

Type

CHARACTER

Default

''

Description

Output file containing deltavscf (not used in calculation)

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filkf

Type

CHARACTER

Default

‘./’

Description

File which contains the fine k-mesh or the k-path of electronic states to be calculated for elinterp. Crystal coordinates.

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filqf

Type

CHARACTER

Default

‘./’

Description

File which contains the fine q-mesh or the q-path of phonon states to be calculated for phinterp. Crystal coordinates.

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filukk

Type

CHARACTER

Default

‘prefix.ukk’

Description

The name of the file containing the rotation matrix U(k) which describes the MLWFs.

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filukq

Type

CHARACTER

Default

‘prefix.ukq’

Description

The name of the file containing the rotation matrix U(k+q) which describes the MLWFs.

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fsthick

Type

REAL

Default

1.d10

Description

Width of the Fermi surface window to take into account states in the self-energy delta functions in [eV]. Narrowing this value reduces the number of bands included in the selfenergy calculations.

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gap_edge

Type

REAL

Default

0.d0

Description

Initial guess for the superconducting gap edge if gap_edge .gt. 0.d0 in [eV]. Otherwise the initial guess for the gap is estimated based on the critical temperature found from the Allen-Dynes formula and BCS ratio (2*gap/T_c=3.52)

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imag_read

Type

LOGICAL

Default

.false.

Description

If .true. read from file the superdconducting gap and renormalization function on the imaginary-axis at a temperature XX. The required file is ‘prefix.imag_aniso_XX’. The temperature should be specified as temps(1) =XX in the input file. This flag works if limag =.true. and laniso =.true., and can be used to:
(1) solve the Eliashberg equations on the real-axis with lpade =.true. or lacon =.true. starting from the imaginary-axis solutions at temperature XX;
(2) solve the Eliashberg equations on the imaginary-axis at temperatures grater than XX using as a starting point the gap estimated at temperature XX.
(3) write to file the superconducting gap on the Fermi surface in cube format at temperature XX. The output file is ‘prefix.imag_aniso_gap_XX_YY.cube’, where YY is the band number within the chosen energy window during the EPW calculation. The file is written if iverbosity =2.

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int_mob

Type

LOGICAL

Default

.false.

Description

If .true. and carrier = .false. it compute the intrinsic mobility such that the electron carrier concentration and hole concentration are the same (only one Fermi level) and give both electron and hole mobility in the same run. If the gap is too big, the number of carrier will be so small that the code will be unstable. If .true. and carrier = .true. it will compute the intrinsic electron and hole mobility with two Fermi level such that the electron and hole carrier concentration is ncarrier.

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iterative_bte

Type

LOGICAL

Default

.false.

Description

If .true. it compute the iterative Boltzmann Transport Equation (IBTE) intrinsic mobility such that the electron carrier concentration and hole concentration are the same (only one Fermi level) and give both electron and hole mobility in the same run. If the gap is too big, the number of carrier will be so small that the code will be unstable. If .true. and carrier = .true. it will compute the intrinsic electron and hole mobility with two Fermi level such that the electron and hole carrier concentration is ncarrier. Also see mob_maxiter.
Note that the IBTE can only be solved on a homogeneous grid. You can use k-point symmetry to reduce the computational time with mp_mesh_k.

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iverbosity

Type

INTEGER

Default

0

Description

0 = short output
1 = verbose output.
2 = verbose output for the superconducting part only.
3 = verbose output for the electron-phonon part only [mode resolved linewidths etc..].

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kerread

Type

LOGICAL

Default

.false.

Description

If .true. read Kp and Km kernels from files .ker when solving the real-axis Eliashberg equations.

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kerwrite

Type

LOGICAL

Default

.false.

Description

If .true. write Kp and Km kernels to files .ker when solving the real-axis Eliashberg equations.

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kmaps

Type

LOGICAL

Default

.false.

Description

Generate the map k+q –> k for folding the rotation matrix U(k+q). If .true., the program reads ‘prefix.kmap’ and ‘prefix.kgmap’ from file. If .false., they are calculated.
Note that for a restart with epwread =.true., kmaps also needs to be set to true (since the information to potentially calculate kgmaps is not generated in a restart run). However, the files “prefix.kmap” and “prefix.kgmap” themselves are actually not used if epwread=.true. and hence need not actually be there.

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lacon

Type

LOGICAL

Default

.false.

Description

If .true. an analytic continuation to continue the imaginary-axis Eliashberg equations to real-axis. This flag requires limag =.true. and lpade =.true.

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laniso

Type

LOGICAL

Default

.false.

Description

If .true. solve the anisotropic Eliashberg equations on the imaginary-axis. To solve the equations, *.ephmat, *.freq, *.egnv, and *.ikmap files should be provided. These files are described under ephwrite variable.

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lifc

Type

LOGICAL

Default

.false.

Description

If .true. uses the real-space inter-atomic force constant generated by q2r.x. The resulting file must be named “ifc.q2r”. The file has to be placed in the same directory as the dvscf files. In the case of SOC, the file must be named “ifc.q2r.xml” and be in xml format. See asr_typ for the type of acoustic sum rules that can be imposed.

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limag

Type

LOGICAL

Default

.false.

Description

If .true. solve the imaginary-axis Eliashberg equations.

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lindabs

Type

LOGICAL

Default

.false.

Description

If .true. computes indirect phonon absorption. See the input variables omegamax, omegamin, omegastep and n_r.

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liso

Type

LOGICAL

Default

.false.

Description

If .true. solve the isotropic Eliashberg equations on the real- or imaginary-axis. To solve the equations provide either: (1) Eliashberg spectral function file using fila2f variable. (2) *.ephmat, *.freq, *.egnv, and *.ikmap files. These files are described under ephwrite variable.

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lpade

Type

LOGICAL

Default

.false.

Description

If .true. Pade approximants to continue the imaginary-axis Eliashberg equations to real-axis. This works with limag =.true.

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lphase

Type

LOGICAL

Default

.false.

Description

If .true. then fix the gauge for the interpolated dynamical matrix and electronic Hamiltonian.

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lpolar

Type

LOGICAL

Default

.false.

Description

If .true. enable the correct Wannier interpolation in the case of polar material.

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lreal

Type

LOGICAL

Default

.false.

Description

If .true. solve the Eliashberg equations directly on the real-axis. Only the isotropic case (liso =.true.) is implemented.

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lscreen

Type

LOGICAL

Default

.false.

Description

If .true. the el-ph matrix elements are screened by the RPA or TF dielectric function. See (scr_typ).

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lunif

Type

LOGICAL

Default

.true.

Description

If .true. a uniform frequency grid is defined between (wsfc,wscut) for solving the real-axis Eliashberg equations. Works only with lreal =.true.

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longrange

Type

LOGICAL

Default

.false.

Description

If .true. only the long-range part of the electron-phonon matrix elements are calculated. Works only with lpolar =.true.

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max_memlt

Type

REAL

Default

2.85d0

Description

Maximum memory that can be allocated per pool in [Gb].

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meff

Type

REAL

Default

12.0

Description

Density of state effective mass for electron-plasmon.

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mob_maxiter

Type

INTEGER

Default

50

Description

Maximum number of iteration during the IBTE.

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mp_mesh_k

Type

logical

Default

.false.

Description

If .true., fine electronic mesh is in the irr. wedge, else a uniform grid throughout the BZ is used.

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mp_mesh_q

Type

logical

Default

.false.

Description

If .true., fine phonon mesh is in the irr. wedge, else a uniform grid throughout the BZ is used. Not currently in use.

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nbndsub

Type

INTEGER

Default

0

Description

Number of wannier functions to utilize.

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ncarrier

Type

REAL

Default

1.0d+13

Description

If carrier = .true. then compute the intrinsic mobility with ncarrier concentration (in cm^-3). If ncarrier is positive it will compute the electron mobility and if it is negative it will compute the hole mobility. If int_mob is also .true. then it will compute both the electron and hole mobility, which is the recommended way to compute mobility.

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nc

Type

REAL

Default

4.0d0

Description

Number of carriers per unit cell that participate to the conduction in the Ziman’s resistivity formula. Typically this corresponds to the number of bands crossing the Fermi level. This can be a fractional number.

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nel

Type

REAL

Default

0.01

Description

Carrier concentration for electron-plasmon.

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nest_fn

Type

LOGICAL

Default

.false.

Description

Calculate the electronic nesting function.

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ngaussw

Type

INTEGER

Default

1

Description

Smearing type for FS average after Wannier interpolation

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nk1, nk2, nk3

Type

INTEGER

Default

0

Description

Dimensions of the coarse electronic grid, corresponds to the nscf calculation and wfs in the outdir.

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nkf1, nkf2, nqf3

Type

INTEGER

Default

0

Description

Dimensions of the fine electron grid, if filkf is not given.

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nq1, nq2, nq3

Type

INTEGER

Default

0

Description

Dimensions of the coarse phonon grid, corresponds to the nqs list.

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nqf1, nqf2, nqf3

Type

INTEGER

Default

0

Description

Dimensions of the fine phonon grid, if filqf is not given.

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nqsmear

Type

INTEGER

Default

10

Description

Number of different smearings used to calculate the a2f.

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nqstep

Type

REAL

Default

500

Description

Number of steps used to calculate the a2f

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n_r

Type

REAL

Default

1.0

Description

Refractive index used when lindabs = .true.

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nsiter

Type

INTEGER

Default

40

Description

Number of iteration for the self-consistency cycle when solving the real- or imaginary-axis Eliashberg equations.

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nsmear

Type

INTEGER

Default

1

Description

Number of different smearings used to calculate the phonon self-energy.

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nstemp

Type

INTEGER

Default

1

Description

Number of temperature points used for superconductivitiy, transport, indabs, etc.. If nstemp is left blank, or is equivalent to the number of entries in temps(:), then the temperatures provided in temps(:) are used. If nstemp>2 and only two temperatures are given in temps(:), then an evenly spaced temperature grid with steps between points given by (temps(2) - temps(1)) / (nstemp-1) is generated. This grid contains nstemp points. nstemp cannot be larger than 50.

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nswi

Type

INTEGER

Default

0

Description

Number of frequency grid points when solving the imaginary-axis Eliashberg equations. If nswi > 0, wscut is ignored. Works only with limag =.true.

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nswc

Type

INTEGER

Default

0

Description

Number of frequency grid points between (wsfc, wscut) when solving the real-axis Eliashberg equations. Works only with lreal=.true.

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nswfc

Type

INTEGER

Default

0

Description

Number of frequency grid points between (0, wsfc) when solving the real-axis Eliashberg equations. Works only with lreal =.true.

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muc

Type

REAL

Default

0.d0

Description

Effective Coulomb potential used in the Eliashberg equations.

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nw

Type

INTEGER

Default

10

Description

Number of bins for frequency scan in delta( e_k - e_k+q - w).

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nw_specfun

Type

INTEGER

Default

100

Description

Number of bins for frequency in electron spectral function.

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omegamax

Type

REAL

Default

10

Description

Photon energy maximum (in eV) when lindabs = .true.

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omegamin

Type

REAL

Default

0

Description

Photon energy minimum (in eV) when lindabs = .true.

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omegastep

Type

REAL

Default

1

Description

Steps in photon energy (in eV) when lindabs = .true.

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outdir

Type

CHARACTER

Default

‘./’

Description

Scratch directory.

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phonselfen

Type

LOGICAL

Default

.false.

Description

Calculate the phonon self-energy from the el-ph interaction.

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plselfen

Type

LOGICAL

Default

.false.

Description

Calculate the electron-plasmon self-energy (model). It requires the definition of nel, meff and epsiHEG.

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prefix

Type

CHARACTER

Default

‘pwscf’

Description

Prepended to input/output filenames. Must be the same used in the calculation of the wfs and phonons.

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prtgkk

Type

LOGICAL

Default

.false.

Description

Allows to print the electron-phonon vertex |g| (in meV) for each q-point, k-point, i-band, j-band and modes.
Note: Average over degenerate i-band, j-band and modes is performed but not on degenerate k or q-points.
Warning: this produces huge text data in the main output file and considerably slows down the calculation.
Suggestion: Use only 1 k-point (like Gamma).

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pwc

Type

REAL

Default

1.0

Description

Power used to define a non-uniform grid between (wsfc, wscut) when solving the real-axis Eliashberg equations. Works only if lreal =.true.

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rand_nq, rand_nk

Type

INTEGER

Default

1

Description

number of random q,k-vectors on the fine mesh

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rand_q, rand_k

Type

LOGICAL

Default

.false.

Description

q/k-vectors on the fine mesh are generated randomly

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restart

Type

LOGICAL

Default

.false.

Description

Create a restart point every restart_step q-points from the fine grid during the interpolation stage.

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restart_step

Type

INTEGER

Default

100

Description

Frequency of restart points during the fine q-grid interpolation phase. This produces restart files called XXX.sigma_restart1

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scr_typ

Type

INTEGER

Default

0

Description

If 0 calculates the Lindhard screening, if 1 the Thomas-Fermi screening. Only relevant if lscreen = .true.

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scattering

Type

LOGICAL

Default

.false.

Description

If .true. computes scattering rates. See also scattering_serta for the type of scattering.

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scattering_serta

Type

LOGICAL

Default

.false.

Description

If .true. computes scattering rates in the self-energy relaxation time approximation. See S. Poncé, E. R. Margine and F. Giustino, Phys. Rev. B 97, 121201 (2018) for more information.

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scissor

Type

REAL

Default

0.0

Description

Gives the value of the scissor shift of the gap (in eV).

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smear_rpa

Type

REAL

Default

0.05d0

Description

Smearing for the calculation of the Lindhard function (in eV). Only relevant if lscreen = .true.

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specfun_el

Type

LOGICAL

Default

.false.

Description

Calculate the electron spectral function from the e-ph interaction. The relevant variables in this case are wmin_specfun, wmax_specfun and nw_specfun.

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specfun_ph

Type

LOGICAL

Default

.false.

Description

Calculate the phonon spectral function from the e-ph interaction. The relevant variables in this case are wmin_specfun, wmax_specfun and nw_specfun.

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specfun_pl

Type

LOGICAL

Default

.false.

Description

Calculate electron-plasmon spectral function. The relevant variables in this case are wmin_specfun, wmax_specfun and nw_specfun. See also nel, meff, epsiHEG.

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system_2d

Type

LOGICAL

Default

.false.

Description

If .true. the system is two-dimensional (vaccum is in z-direction) and the k and q meshes are defined in the xy-plane.

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temps

Type

REAL(nstemp)

Default

300.d0

Description

Temperature values used in superconductivitiy, transport, indabs, etc.. If no temps are provided, temps=300 and nstemp =1. If two temps are provided, with temps(1)<temps(2) and nstemp >2, then temps is transformed into an evenly spaced grid with nstemp points, including temps(1) and temps(2) as the minimum and maximum values, respectively [Ex) nstemp      =   5 temps       = 300 500]. In this case, points are spaced according to (temps(2) - temps(1)) / (nstemp-1). Otherwise, temps is treated as a list, with the given temperatures used directly [Ex) temps    = 17 20 30]. No more than 50 temperatures can be supplied in this way.

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vme

Type

LOGICAL

Default

.false.

Description

If .true. then calculate the velocity matrix elements beyond the local approximation.

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wannierize

Type

LOGICAL

Default

.false.

Description

Calculate the Wannier functions using W90 library calls and write rotation matrix to file ‘filukk’. If .false., filukk is read from disk.

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wepexst

Type

LOGICAL

Default

.false.

Description

If .true. then prefix.epmatwe files are already on disk (don’t recalculate). This is a debugging parameter.

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wmax

Type

REAL

Default

0.3d0

Description

Max frequency in delta( e_k - e_k+q - w).

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wmax_specfun

Type

REAL

Default

0.d0

Description

The upper boundary for the frequency in the electron spectral function in [eV].

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wmin

Type

REAL

Default

0.d0

Description

Min frequency in delta( e_k - e_k+q - w).

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wmin_specfun

Type

REAL

Default

0.d0

Description

The lower boundary for the frequency in the electron spectral function in [eV].

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wscut

Type

REAL

Default

1.d0

Description

Upper limit over frequency integration/summation in the Eliashberg equations in [eV]. For limag =.true., wscut is ignored if the number of frequency points is given using variable nswi.

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wsfc

Type

REAL

Default

0.5 * wscut

Description

Intermediate frequency between (0, wscut) in the integration of the real-axis Eliashberg equations in [eV]. Works only with lreal =.true.

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nqs

Variable

Type

INTEGER

Description

The number of phonon points listed below.

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xq(1)  xq(2)  xq(3)

Type

REAL

Description

The phonon wavevectors of the coarse grid. Must be in the same order as prefix_q* listed in dvscf_dir

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dis_froz_min, dis_froz_max

Type

REAL

Default

-1d3, -0.9d3

Description

Window which includes frozen states for Wannier90. See wannier90 documentation.

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dis_win_min, dis_win_max

Type

REAL

Default

-1d3, 1d3

Description

Minimum and maximum values of the disentanglement window. See wannier90 documentation.

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iprint

Type

INTEGER

Default

2

Description

Verbosity level of Wannier90 code. See wannier90 documentation.

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num_iter

Type

INTEGER

Default

200

Description

Number of iterations passed to Wannier90 for minimization. See wannier90 documentation.

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proj(:)

Type

CHARACTER

Default

''

Description

Initial projections used in the Wannier90 calculation. Simple solution is proj(1) = 'random'. See wannier90 documentation.

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wdata(:)

Type

CHARACTER

Default

''

Description

Any extra inforumation to be used in the Wannier90 calculation should be included here. These characters will be written to the ‘prefix.win’ file. For example to plot the first Wannier function in xcrysden format:
—————————————————–
wdata(1) = 'wannier_plot = true'
wdata(2) = 'wannier_plot_list : 1'
—————————————————–
See wannier90 documentation.

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write_wfn

Type

LOGICAL

Default

.false.

Description

If .true. UNK files are output. These files must be on disk if wannier_plot = .true.